Aminohydroxybenzophenones and triazine derivatives thereof



7 This invention relates to new triazine derivatives of benzophenones.More specifically it relates to compounds of the formula in which D isthe structure iwherein A may be hydrogen or hydroxyl and B may behydrogen, lower alkyl, alkoxy, chlorine or bromine, and B may bechlorine, the1group:-NHD wherein D is defined above, sulfoalkylamino orcarboxyalkylamino.

It has been demonstrated that ultraviolet light has a tendency to causethe deterioration of cellulose, whether in the form of sheets ofregenerated cellulose or in the form of natural or regenerated fibers.This has been shown by protecting the fibers with ultraviolet lightabsorbing screens and measuring the decrease in deterioration uponexposure of ultraviolet light. Means have therefore been sought toprotect the fibers by the utilization of ultraviolet absorbingcompounds. One way sug- ,gested is to incorporate ultraviolet absorbingcompounds "in resin latices and use these latices in the resin treatmentof the fibers. Since the absorbing power of films decreases as theybecome thinner, this has proved to be a very inefficient method becausea film of the thickness whichcan be tolerated on the fiber screens outonly a very small, amount of ultraviolet radiation. 7

We have found a much more satisfactory solution to this problem in thatwe have devised a way of making the benzophenone ultravioletiightabsorber an integral part of the cellulose molecule. We achievethis object by esterifying the hydroxyls of the cellulose molecule aminimum of .0l% of the hydroxylsbeing esterified with a class ofchlorotriazinylaminobenzophenones, such modi;

fied cellulose being claimed in our copending application Serial No.39,424 filed lune 29, 1960. This class of triazinylaminobenzophenones asdefined below is the invention herein claimed. We have also found a newclass Aminobenzophenone derivative The aminobenzophenone intermediatesfor our invention are characterized by the formula r i V $11 in which Amay be hydrogen or hydroxyl and in which B may be hydrogen, alkyl,alkoxy or halogen.

These compounds are prepared by reacting a paranitrobenzoyl chloridewith the properly substituted anisole in the presence of aluminumchloride and simultaneously demethylating the resulting intermediate byheating. There is thus formed the 4-nitrobenzophenone which can bereadily reduced to form the corresponding 4-aminobenzophenone. Thispreparation can be illustrated by the following schematic equationinwhich A and B have the same meaning as above.

Since-A can be hydrogen or hydroxyl, the benzoyl chloride startingmaterial may be 4-nitrobenzoyl chloride or 4- nitrosalicyloyl chloride.

The other reagent can be meta or para halogen, alkoxy or alkylderivatives of anisole. In the case of a metaalkoxy anisole (that is adialkyl resorcinol), only the alkoxy which is ortho to the carbonyl isdealkylated in the preparation of our invention under conditions used.Thus for example, 4-nitrobenzoyl chloride and metadimethoxybenzene whenreacted in mono-chlorobenzene solution in the presence of aluminumchloride and the reaction mixture subsequently is heated to form4-nitro-2- hydroxy-4-methoiiybenzophenone.

Other alkoxybenzenes which may be used include mdimethoxybenzene,m-diethoxybenzene, m-chloranisole, m-bromoanisole, m-methylanisole,m-propylanisole and the like. a

An alternative synthesis for these compounds is to prepare 4-nitro diortrihydroxybenzophenones and alkyla'te' nitrobenzoic acid orp-nitrosalicylic acid can be condensed with resorcinol in the presenceof borontrifluoride.

Alkylation of the resulting 4-nitro-2,4-dihydroxybenzor phenone or4-nitro-2,2',4-trihydroxybenzophenone with an alkylating agentresults'in the 4-alkoxy compound, e'.g.,'

The nitro group can now be reduced to give the amino compound.Alkylating agents which can be used include dietliylsulfate, butylbromide, isobutyl bromide octyl bromide, t-octyl bromide, lauryl bromideand octadecyl bromide, "as well as the but yl, lauryl, hexadecyl, oroctadecyl esters of p-toluenesulfonic acid. It is generally preferableto prepare the 4- or S-alkoxybenzophenones with alkyls above methyl bythis route.

Reduction of the nitro compound gives the 4'-amino-2-hydroxybenzophenones of the general formula .given above. This reductioncan be carried out in any known way, either catalytically or withreducing agents such as sodium sulfide, iron and acetic acid and thelike. Catalytic reduction is carried out in usually over palladium oncharcoal.

These aminobenzophenones are claimed in our patent application. They areuseful, as will be described, in the preparation of thetriazinylaminobenzophenones of our invention and also of the esterifiedcellulose claimed in another application. Our invention claimed hereinis chlorotriazinylarninohydroxybenzophenones of the formula,

in which D represents the structure @iC A $11 wherein A may be hydrogenor hydroxyl and B may be hydrogen, lower alkyl, alkoxy, chlorine, orbromine, and E represents either chlorine, the group -NHD, in which D isas defined above, sulfoalkylamino or carboxyalkylamino. Such compoundsare formed by the reaction of cyanuric chloride with theaminohydroxybenzophenones described above. For example, cyanuricchloride and 4'- amino-2-hydroxybenzophenone react in acetone at roomtemperature to form a mixture of 2,4-dichloro-6-[4-(2- hydroxy 4methoxybenzoyl)anilinoJ-s-triazine and 2- chloro-4,6-bis[4 (2 hydroxy 4methoxybenzoyDanilino]-s-triazine. These two compounds are easilyseparable by fractional crystallization. If the reaction is carried outat lower temperatures the product is almost exclusively the 2,4-dichloroderivative. At higher temperatures and with an excess of aminohydroxybenzophenone a good yield of the bis-aniline triazine isobtained. The other amino benzophenones discussed under that topic abovecan similarly be used. Such amino benzophenones include 4'-amino 2hydroxybenzophenone, 4'-amino-2-hydroxy 4 methylbenzophenone, 4'- amino2 hydroxy 4 ethoxybenzophenone, 4-amino- 2,2-dihydroxybenzophenone, 4'amino-2,2-dihydroxy- 4-methoxybenzophenone, 4'amino-2-hydroxy-4-chlorobenzophenone,-4'-amino 2,2dihydroxy-4-chlorobenzophenone and the like, as well .as the othervariations and permutations permissible in the aminohydroxybenzophenoneas defined above. In each case either one or .two chlorines of thecyanuric chloride can be replaced by an aminohydroxyphenone.

The dichlorotriazinylaminobenzophenone compounds of our invention may befurther modified by reaction with one mol of an aminoalkane sulfonicacid or an aminoalkyl carboxylic acid. Thus, for example,2,4-dichloro-6-[4-(2-hydroxy 4 methoxybenzoyl) anilino]-striazine.Similarly, other amino acids can be used in place of the taurine, suchas glycine, alanine, serine, 3- aminopropionic acid, 3aminopropanesulfonic acid, 4- amino butanesulfonic acid and the like.The chlorotriazinylaminobenzophenones of our invention, which also have,as a second substituent on the triazine ring, an aminoalkyl acid of thisnature, are more easily applied to fibers and give better results.Consequently, they are a preferred species.

The chlorotriazinylhydroxybenzophenone compounds of our invention can beapplied to cellulosic materials d to yield a product protected againstthe deteriorating effect of ultraviolet light.

They can be applied like a dyestutf, especially those modificationshaving a carboxyalkylamino or sulfoalkylamino substituent on thetriazine ring. The cellulosic materials may be dyed later or they may bedyed before being treated with the chlorotriazinehydroxybenzophenones ofthis invention. In some cases the dyestufi and the benzophenone compoundmay be applied simultaneously. In each case a material is obtained whichhas a high capacity for absorbing ultraviolet light and which retainsits capacity through repeated washing.

Modified cellulose A further embodiment of our invention claimed in acompanion case, is the cellulose modified by having at least 0.01% ofits free hydroxyl groups esterified with achlorotriazinylaminobenzophenone of the above definition. While thechlorotriazinylaminobenzophenone described above can be used in manycases like ordinary dyes, when they are applied to the fiber in analkaline medium it has been found that they are capable of reaction withthe hydroxyls of the cellulose to form esters. These modified cellulosepolymers form this embodiment of our invention. They are cellulosehaving as an integral part of its molecule a built-in ultraviolet lightstabilizer. Such cellulose not only is more stable than ordinarycellulose but also the ultraviolet light stabilizer built into thecellulose molecule gives added protection to dyestufis placed upon thefiber rendering them more light fast also.

The modified cellulose is obtained by treating cellulose with thechlorotriazinylamino benzophenones of our invention of the typesdescribed above, in alkaline medium at elevated temperatures. Thebenzophenone derivative can be put on the cellulose in advance of theheating with alkali or simultaneously with this treatment. A minimum ofF. is needed to effect the chemical combination within a reasonabletime. A more practical range is about l40-160 F. where desired reactionis complete in about 15 minutes. The alkali used may be a strong alkali(NaOH, KOH, LiOH, Ca(OII) or a weaker acid binder (soda ash, potash andthe like). Sutficient is used to neutralize all the hydrogen chlorinewhich theoretically could be evolved from the benzophenone compound usedand still keep the mixture alkaline.

At least 0.01% of the total hydroxyls in the cellulose molecule shouldbe esterified to achieve effective protection against ultraviolet light.

The cellulose may be in the form of fibers or in the form of sheets. Itmay be natural cellulose or regenerated cellulose, it may be in the formof cotton, linen, hemp, jute, rayon, cellophane, or the like.

Our invention can be illustrated by the following examples in whichparts are by weight unless otherwise specified.

EXAMPLE 1 p-Nitrobenzoylchloride (90.8 parts), m-dimethoxybenzene (69parts) and monochlorbenzene (333.2 parts) are mixed and cooled to 15 C.Aluminum chloride (84 parts) is added gradually while maintaining thetemperature below 15 C. The mixture is then stirred at 10 for a shortperiod. It is then gradually allowed to warm to 25 C. after which it isheated on a steam bath at 90 C. until the reaction is complete. Themixture is then drowned in ice water (700 parts) and the drowned mixtureis heated on a steam bath to decompose the complex. It is then allowedto cool and the crystals which form are filtered ofi, recrystallizedfrom a mixture of 1224 parts of alcohol and 219.75 parts of benzene, filtered and dried.

EXAMPLE 2 9 2-hydroxy-4-methoxy-4'-nitrobenzophenone (25 parts), glacialacetic acid (104.98 parts), and 10% palladium on charcoal (about 0.1part) are placed in a hydrogenation autoclave. Hydrogen is run to 40 lb.pressure and the clave is shaken until a pressure drop of abouttwentythree pounds occurs. The mixture is then heated on the streambath, treated with acetone (79.2 parts), filtered, and the filtratedrowned in water (500 parts). The yellow solid which forms is filtered,washed with Water, oven dried at 50 C. and recrystallized from alcoholto yield 4'-amino-2-hydroxy 4 methoxybenzophenone.

' EXAMPLE 3 EXAMPLE 4 V EXAMPLE 6 5 on on The procedure of Example 1 isrepeated using an equivalent quantity of p-nitrosalicyloyl chloride inplace of the p-nitrobenzoylchloride. The p-nitrosalicyloyl chloride maybe prepared by heating p-nitrosalicylic acid with excess thionylchloride using a small amount of pyridine as a catalyst.

EXAMPLE 7 t HzNQCQ-OCH:

" on on The'procedure of Example 2 is followed using as startingmaterial the product of Example 6.

EXAMPLE 8 II V 01% Jan1QoQ-oom H on 1 The procedure of Example 3 isfollowed using the product of Example 7 in place of the4-amino-2-hydroxy- 4-methoxybenzophenone.

EXAMPLE 9 A sample of cellophane film (0.1734 gram) is placed in 50 ml.of a solution of 0.0259 gram of 2,4-dichloro- 6- [4-2-hydroxy-4-methoxybenzoyl anilino -s-triazine in acetone. After onehalf hour, 100 ml. of a developing solution (10 parts of soda ash and 60parts of sodium chloride to 1000 parts of water) are poured into theacetone-cellophane bath. After one hour, the sample H I ll OH N OH Theprocedure of Example 3 is followed except that twice the quantity of the4'-amino-2-hydroxy-methoxybenzophenone is used and the acetone solutionis heated to reflux until the reaction is substantially complete..-

EXAMPLE 5 of cellophane is removed-from the bath, rinsed, dried andtested spectrophotometrically. The sample shows an absorption peak at333 m with an absorbency of 0.312. The curve of a 0.0026% solution of2,4-dichloro- 6-[4-(2-hydroxy-4-methoxybenzoyl)aniline]-s-triazine inacetone also showed an absorption peak at 333 mg. with an absorbency of0.996. This indicates that a washfast reaction product has been formedbetween the cellophane and the 2,4-dichloro-6-[4-(2-hydroxy-4-methoxy)-anilinel-s-triazine when they are combined in an acetonealkaline aqueousbath. Knowing that the cellophane is 0.023 centimeter thick and has adensity of 1.45, the percent by weight of the triazine derivative on thecellophane is-calculated to be about 0.02%.

EXAMPLE 10 OH A I p-Nitrobenzoic acid (167 parts), resorcinol (110parts), and monochlorobenzene (1000 parts) are slurried and heated to 50C. Heating is discontinued and boron trifluoride (136 parts) is added.The temperature is raised to -100 C. and the mixture is stirred at thistemperature until reaction is substantially complete. The mixture isdrowned in a solution consisting of sodium acetate (200 parts) and water(1000 parts) and stirred a short while at 90100 C. The solvent isremoved by steam distillation. The residue is cooled and recrystallizedfrom benzene.

EXAMPLE 11 By reduction of the product of Example 11 using the proceduresimilar to that described in Example 2,2-hydroxy-4-butoxyl-aminobenzophenone is obtained.

Corresponding homologous products are obtained by a similar procedure.

EXAMPLE 13 nmQ-o o-Q-cn The procedure of Example 1 is followed using anequivalent quantity of m-chloranisole in place of the dimethoxybenzene.The product is reduced by the procedure of Example 2.

Similarly, the use of m-methylanisole and m-bromoanisole in thisprocedure results in the correspondingly substituted product.

EXAMPLE 14 ClfiNHQC oQ-ox 01 The procedure of Example 3 is followed,using an equivalent quantity of the product of Example 13 instead ofthat of Example 2.

The fixing or reacting of this compound on the padded cotton is obtainedby immersing the cloth in a solution containing 50 milliliters of 30 B.caustic and 300 g. of sodium chloride per liter at 140 to 160 F. for 15minutes. The fabric is then rinsed, soaped and dried. The amount ofultraviolet absorber reacted with the cotton is determined by analysisfor sulfur and nitrogen, is found to be about 0.63%, equivalent to0.125% of the free hydroxys. This is about 34% of the absorberoriginally padded on the cloth.

A piece of this treated cotton cloth is dyed with 0.25% of a yellow dye.An untreated cotton sample is dyed likewise. Exposure of both pieces ofdyed cloth in a Fade-O-meterproduced less fading of the treated yellowcloth.

We claim:

1. Compound of the-formula wherein E is selected from the groupconsisting of chlorine, lower sulfoalkylamino, 'lower carboxyalkylamino,lower sulfoalkoxy, lower carboalkoxy and the Structure .nnQ Q-B N N 'CEEO-QC OQNHlNy -NH-CIHtS OaNa omoQo OQNHlNj NHQCOQO on. o n 611 EXAMPLE15 through the padding solution and through a wringer to I remove excesssolution. The cloth is dried at room temperature. Analysis indicates0.0185 gram of compound per gram of padded fabric.

or I

1. COMPOUND OF THE FORMULA